The invention concerns a modular abrasive agent water jet cutting head with specific abrasive agent additions.
It is known to mix an abrasive agent such as garnet or corundum into the cutting water jet in order to increase the cutting effect of the cutting water jet. For this the abrasive agent in a mixing chamber, through which the water jet flows vertically, is fed to the water jet from the side as uniformly as possible over the entire circumference (EP 221236).
It is known that the mixing chamber can be protected with deposited abrasive agent in order to avoid erosion in the mixing chamber due to the abrasive material, (DE-OS 384434) so that the abrasive agent is washed specifically and directly into the water jet by injection water. In order to reinforce this, the abrasive agent is accelerated at an acute angle (DE-GM 9402916.9) and added to the mixing chamber under pressure (DE-OS 4005691).
In order to protect the focussing nozzle from the effect of the abrasive agent, the cutting jet is surrounded with a water jacket (DE-OS 4005691). For better mixing of the abrasive agent into the water jet it is known to expand the focussing nozzle in funnel-shape on the inlet side (EP 110529).
According to DE-OS 3516103 a cutting jet loaded uniformly with abrasive particles is a condition for a clean, uniform cut. In the case of non-uniform distribution of the particles on one side in the mixing chamber, and thus undirected particle feed to the circumference of the previously described cutting heads flowing through the mixing chamber centrally, there is no uniform particle jet, as is desired. An asymmetrically loaded mixing jet can cause a non-uniform cut and a one-sided wear of the focussing nozzle.
Precise investigations have shown that only the abrasive particles located on the surface in the direction of cut of the mixed jet produce a cutting effect. The abrasive particles located in the interior or on the sides of the jet turned away from the direction of cutting do not produce a cutting effect.
The purpose and task of the invention is to apply abrasive particles on the surface of the cutting jet, in the respective direction of cutting thus in order to increase the cutting power with a reduction of the use of the abrasive agent.